1. Field of the Invention
The present invention relates to an imaging apparatus employing an improved method for reading signals from a photodetective area of an imaging device.
Priority is claimed on Japanese Patent Application No. 2006-43566, filed Feb. 21, 2006, the content of which is incorporated herein by reference.
2. Description of the Related Art
Some imaging apparatuses have a function of changing the frame rate in accordance with use (see, for example, Japanese Patent No. 3129599). In video photography, when the frame rate is changed in accordance with the movement of a subject and it is converted to a specific rate for display (i.e., a display frame rate) so as to reproduce images, natural slow motion or high-speed motion video images can be displayed. For example, when images are captured using a frame rate higher than the display frame rate, and the frame rate of the images is then converted in conformity with the display frame rate, slow-motion reproduced images are displayed, and in the converse case, high-speed reproduced images are displayed.
In such cases, it may be unnecessary to process the whole area of one image frame at the same frame rate, for example, when a specific subject moves on a background which almost stands still. In order to perform photography at a high frame rate in accordance with the speed of a moving subject, when signals are read at the same high-speed frame rate from the whole image area of each image frame, almost the same image data of the background which almost stands still is also obtained several times over a plurality of image frames, and is sequentially processed in the following circuit.